All five European Vacuum Vessel sectors are under fabrication

Parts placed together before assembly of the segment PS3 for the first VV sector, sector 5, at Walter Tosto.

The production of all five Vacuum Vessel sectors that Europe is producing for ITER is currently progressing well. This parallel production of such a large number of geometrically complex mechanical sectors in ITER grade stainless steel is in contrast to last year's production of one sole sector and shows the commitment of F4E to the ITER project.

With contractors and subcontractors within the Vacuum Vessel consortium, located across Europe: CNIM (France), ENSA (Spain), MAN (Germany), ProBeam (Germany), Belleli (Italy), Mangiarotti (IT), Walter Tosto (IT), Ansaldo Nucleare (IT), the consortium has vastly increased its manufacturing capacity and has already proven in its early stages its drive to deliver. Fabrication consists of the following steps: qualification, manufacturing design, material procurement, machining into the correct shapes, welding of the parts to form bigger the sectors for the Vacuum Vessel – each of the five sectors is at a different stage of fabrication but definitely moving forward. Notable in terms of qualification, is that in part due to the past experience, CNIM has been able to qualify its welding techniques according to the nuclear code in less than two months, a record in comparison to earlier welding qualification times.

The increased production speed is also due to the improvement seen in the preparatory activities leading to better quality welding used to join the different pieces that make up the Vacuum Vessel sectors. "We have been able to hone the welding techniques, thus allowing us to complete welding more rapidly and with a better end-result", says Francesco Zacchia, Project Manager of the Vacuum Vessel Team.

The manufacturing of the Vacuum Vessel sectors is time-consuming and labour intensive due to their geometry and size, where each one measures 6.5 metres high, 3 metres wide and 6.3 metres deep, and weighs around 500 tonnes. The ITER Vacuum Vessel sectors are unique, as despite being made of stainless steel, they will have complex shapes, thus resulting in a most challenging design and manufacture. "The shape of the Vacuum Vessel sectors is far more sophisticated and delicate than what is usually the case for components made of stainless steel where the shapes are usually more conventional", says Max Febvre, manufacturing coordinator of the Vacuum Vessel Team.

This proves Europe's industrial capacity to produce this type of mechanical, high-quality component which needs to follow stringent rules in terms of design, manufacturing and materials in order to adhere to international nuclear rules, as well as developing new technologies to automate and improve the quality of the final end-result. The know-how accumulated during this process is key in increasing Europe's competitiveness in the nuclear and mechanical engineering fields. The simultaneous production of all five sectors is a big milestone for the ITER project and shows that F4E is able to manage the large workload involved in delivering Europe's ITER Vacuum Vessel contribution.

The W subassembly for Poloidal Segment 2 Sector 5 ready for Electron Beam Welding, which has now been completed.